[Federal Register Volume 63, Number 131 (Thursday, July 9, 1998)]
[Proposed Rules]
[Pages 37072-37074]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 98-18159]


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Proposed Rules
                                                Federal Register
________________________________________________________________________

This section of the FEDERAL REGISTER contains notices to the public of 
the proposed issuance of rules and regulations. The purpose of these 
notices is to give interested persons an opportunity to participate in 
the rule making prior to the adoption of the final rules.

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Federal Register / Vol. 63, No. 131 / Thursday, July 9, 1998 / 
Proposed Rules

[[Page 37072]]


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DEPARTMENT OF TRANSPORTATION

Federal Aviation Administration

14 CFR Part 39

[Docket No. 98-NM-72-AD]
RIN 2120-AA64


Airworthiness Directives; Boeing Model 737-100 and -200 Series 
Airplanes

AGENCY: Federal Aviation Administration, DOT.

ACTION: Notice of proposed rulemaking (NPRM).

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SUMMARY: This document proposes the supersedure of an existing 
airworthiness directive (AD), applicable to certain Boeing Model 737-
100 and -200 series airplanes, that currently requires replacement of 
certain outboard and inboard wheel halves with improved wheel halves; 
cleaning and inspecting certain outboard and inboard wheel halves for 
corrosion, missing paint in large areas, and cracks; and repair or 
replacement of the wheel halves with serviceable wheel halves, if 
necessary. That AD was prompted by a review of the design of the flight 
control systems on Model 737 series airplanes. This action would 
require that the actions be accomplished in accordance with revised 
service information. The actions specified by the proposed AD are 
intended to prevent failure of the wheel flanges, which could result in 
damage to the hydraulics systems, jammed flight controls, loss of 
electrical power, or other combinations of failures; and consequent 
reduced controllability of the airplane.

DATES: Comments must be received by August 24, 1998.

ADDRESSES: Submit comments in triplicate to the Federal Aviation 
Administration (FAA), Transport Airplane Directorate, ANM-114, 
Attention: Rules Docket No. 98-NM-72-AD, 1601 Lind Avenue, SW., Renton, 
Washington 98055-4056. Comments may be inspected at this location 
between 9:00 a.m. and 3:00 p.m., Monday through Friday, except Federal 
holidays.
    The service information referenced in the proposed rule may be 
obtained from Allied Signal Aerospace Company, Bendix Wheels and Brakes 
Division, South Bend, Indiana 46624; and Bendix, Aircraft Brake and 
Strut Division, 3520 Westmoor Street, South Bend, Indiana 46628-1373. 
This information may be examined at the FAA, Transport Airplane 
Directorate, 1601 Lind Avenue, SW., Renton, Washington.

FOR FURTHER INFORMATION CONTACT: David Herron, Aerospace Engineer, 
Systems and Equipment Branch, ANM-130S, FAA, Transport Airplane 
Directorate, Seattle Aircraft Certification Office, 1601 Lind Avenue, 
SW., Renton, Washington 98055-4056; telephone (425) 227-2672; fax (425) 
227-1181.

SUPPLEMENTARY INFORMATION:

Comments Invited

    Interested persons are invited to participate in the making of the 
proposed rule by submitting such written data, views, or arguments as 
they may desire. Communications shall identify the Rules Docket number 
and be submitted in triplicate to the address specified above. All 
communications received on or before the closing date for comments, 
specified above, will be considered before taking action on the 
proposed rule. The proposals contained in this notice may be changed in 
light of the comments received.
    Comments are specifically invited on the overall regulatory, 
economic, environmental, and energy aspects of the proposed rule. All 
comments submitted will be available, both before and after the closing 
date for comments, in the Rules Docket for examination by interested 
persons. A report summarizing each FAA-public contact concerned with 
the substance of this proposal will be filed in the Rules Docket.
    Commenters wishing the FAA to acknowledge receipt of their comments 
submitted in response to this notice must submit a self-addressed, 
stamped postcard on which the following statement is made: ``Comments 
to Docket Number 98-NM-72-AD.'' The postcard will be date stamped and 
returned to the commenter.

Availability of NPRMs

    Any person may obtain a copy of this NPRM by submitting a request 
to the FAA, Transport Airplane Directorate, ANM-114, Attention: Rules 
Docket No. 98-NM-72-AD, 1601 Lind Avenue, SW., Renton, Washington 
98055-4056.

Discussion

    On August 4, 1997, the FAA issued AD 97-17-01, amendment 39-10102 
(62 FR 43067, August 12, 1997), applicable to certain Boeing Model 737-
100 and -200 series airplanes, to require replacement of certain 
outboard and inboard wheel halves with improved wheel halves; cleaning 
and inspecting certain outboard and inboard wheel halves for corrosion, 
missing paint in large areas, and cracks; and repair or replacement of 
the wheel halves with serviceable wheel halves, if necessary. That 
action was prompted by a review of the design of the flight control 
systems on Model 737 series airplanes. The requirements of that AD are 
intended to prevent failure of the wheel flanges, which could result in 
damage to the hydraulics systems, jammed flight controls, loss of 
electrical power, or other combinations of failures; and consequent 
reduced controllability of the airplane.

Explanation of Revised Service Information

    Since the issuance of that AD, the FAA has been advised that Allied 
Signal Service Bulletin No. 737-32-026, dated April 26, 1988, which was 
referenced as the appropriate source of service information for 
accomplishment of the actions specified in that original AD, was 
incorrect. Subsequently, the FAA has reviewed and approved Allied 
Signal Service Bulletin No. 737-32-026, dated June 27, 1988. The 
procedures described in that revision are similar to those described in 
the earlier version of the service bulletin. However, among other 
things, this new version of the service bulletin differs from the 
original version in the following respects:
    1. The effectivity listing in the revised service bulletin includes 
a new part number for inboard wheel halves.
    2. The revised service bulletin provides a new option for 
repainting the wheels.
    3. The revised service bulletin identifies specific serial numbers 
of wheel halves on which ``beef-ups'' were

[[Page 37073]]

accomplished, but inspections are still necessary.
    Accomplishment of the actions specified in the service bulletin is 
intended to adequately address the identified unsafe condition.

Explanation of Requirements of Proposed Rule

    Since an unsafe condition has been identified that is likely to 
exist or develop on other products of this same type design, the 
proposed AD would supersede AD 97-17-01 to continue to require 
replacement of certain outboard and inboard wheel halves with improved 
wheel halves; cleaning and inspecting certain outboard and inboard 
wheel halves for corrosion, missing paint in large areas, and cracks; 
and repair or replacement of the wheel halves with serviceable wheel 
halves, if necessary. The actions would be required to be accomplished 
in accordance with the revised service bulletin described previously.

Cost Impact

    There are approximately 634 Boeing Model 737-100 and -200 series 
airplanes of the affected design in the worldwide fleet. The FAA 
estimates that 241 airplanes of U.S. registry would be affected by this 
proposed AD.
    Because this proposed AD would merely require that the actions 
currently required by AD 97-17-01 be accomplished in accordance with 
revised service information, the proposed AD would add no additional 
costs, and would require no additional work to be performed by affected 
operators. The current costs associated with this amendment are 
reiterated in their entirety (as follows) for the convenience of 
affected operators.
    The FAA estimates that it will take approximately 4 work hours per 
airplane to accomplish the required replacement of wheel halves at an 
average labor rate of $60 per work hour. Required parts will cost 
approximately $20,212 per airplane. Based on these figures, the cost 
impact of the required replacement on U.S. operators is estimated to be 
$4,928,932, or $20,452 per airplane.
    The FAA also estimates that it will take approximately 2 work hours 
per airplane to accomplish the required cleaning and inspection at an 
average labor rate of $60 per work hour. Based on these figures, the 
cost impact of the required cleaning and inspection on U.S. operators 
is estimated to be $28,920, or $120 per airplane.

Regulatory Impact

    The regulations proposed herein would not have substantial direct 
effects on the States, on the relationship between the national 
government and the States, or on the distribution of power and 
responsibilities among the various levels of government. Therefore, in 
accordance with Executive Order 12612, it is determined that this 
proposal would not have sufficient federalism implications to warrant 
the preparation of a Federalism Assessment.
    For the reasons discussed above, I certify that this proposed 
regulation (1) is not a ``significant regulatory action'' under 
Executive Order 12866; (2) is not a ``significant rule'' under the DOT 
Regulatory Policies and Procedures (44 FR 11034, February 26, 1979); 
and (3) if promulgated, will not have a significant economic impact, 
positive or negative, on a substantial number of small entities under 
the criteria of the Regulatory Flexibility Act. A copy of the draft 
regulatory evaluation prepared for this action is contained in the 
Rules Docket. A copy of it may be obtained by contacting the Rules 
Docket at the location provided under the caption ADDRESSES.

List of Subjects in 14 CFR Part 39

    Air transportation, Aircraft, Aviation safety, Safety.

The Proposed Amendment

    Accordingly, pursuant to the authority delegated to me by the 
Administrator, the Federal Aviation Administration proposes to amend 
part 39 of the Federal Aviation Regulations (14 CFR part 39) as 
follows:

PART 39--AIRWORTHINESS DIRECTIVES

    1. The authority citation for part 39 continues to read as follows:

    Authority: 49 U.S.C. 106(g), 40113, 44701.


Sec. 39.13  [Amended]

    2. Section 39.13 is amended by removing amendment 39-10102 (62 FR 
43067, August 12, 1997), and by adding a new airworthiness directive 
(AD), to read as follows:

Boeing: Docket 98-NM-72-AD. Supersedes AD 97-17-01, amendment 39-
10102.

    Applicability: Model 737-100 and -200 series airplanes equipped 
with Bendix main wheel assemblies having part number (P/N) 2601571-
1, certificated in any category.

    Note 1: This AD applies to each airplane identified in the 
preceding applicability provision, regardless of whether it has been 
modified, altered, or repaired in the area subject to the 
requirements of this AD. For airplanes that have been modified, 
altered, or repaired so that the performance of the requirements of 
this AD is affected, the owner/operator must request approval for an 
alternative method of compliance in accordance with paragraph (c) of 
this AD. The request should include an assessment of the effect of 
the modification, alteration, or repair on the unsafe condition 
addressed by this AD; and, if the unsafe condition has not been 
eliminated, the request should include specific proposed actions to 
address it.

    Compliance: Required as indicated, unless accomplished 
previously.
    To prevent failure of the wheel flanges, which could result in 
damage to the hydraulics systems, jammed flight controls, loss of 
electrical power, or other combinations of failures; and consequent 
reduced controllability of the airplane; accomplish the following:

    Note 2: Allied Signal, Aircraft Landing Systems, Service 
Information Letter (SIL) #619, dated February 26, 1997, is an 
additional source of service information for appropriate wheel half 
serial numbers.

    (a) For airplanes equipped with a Bendix main wheel assembly 
having P/N 2601571-1 with an inboard wheel half with serial number 
(S/N) B-5898 or lower, or S/N H-1721 or lower; or with an outboard 
wheel half with S/N B-5898 or lower, or S/N H-0863 or lower; 
accomplish the following:
    (1) Within 180 days after September 16, 1997 (the effective date 
of AD 97-17-01, amendment 39-10102, 62 FR 43067), and thereafter at 
each tire change until the replacement required by paragraph (b) of 
this AD is accomplished: Accomplish the actions specified in 
paragraphs (a)(1)(i), (a)(1)(ii), and (a)(1)(iii) of this AD, in 
accordance with the Accomplishment Instructions of Allied Signal 
Service Bulletin No. 737-32-026, dated June 27, 1988.
    (i) Clean any inboard and outboard wheel half specified in 
paragraph (a) of this AD. And
    (ii) Inspect the wheel halves for corrosion or missing paint. If 
any corrosion is found, or if any paint is missing in large areas, 
prior to further flight, strip or remove paint, and remove any 
corrosion. And
    (iii) Perform an eddy current inspection to detect cracks of the 
bead seat area.
    (2) If any cracking is found during the inspections required by 
this paragraph, prior to further flight, repair or replace the wheel 
halves with serviceable wheel halves in accordance with procedures 
specified in the Component Maintenance Manual.
    (b) For airplanes equipped with a Bendix main wheel assembly 
having P/N 2601571-1 with an inboard wheel half with S/N B-5898 or 
lower, or S/N H-1721 or lower; or with an outboard wheel half with 
S/N B-5898 or lower, or S/N H-0863 or lower; accomplish the 
following: Within 2 years after September 16, 1997, accomplish the 
actions specified in paragraphs (b)(1) and (b)(2) of this AD, in 
accordance with Bendix SIL 392, Revision 1, dated November 15, 1979. 
Accomplishment of the replacement constitutes terminating action for 
the repetitive inspections required by paragraph (a) of this AD.
    (1) Remove any inboard wheel half specified in paragraph (b) of 
this AD, and

[[Page 37074]]

replace it with an inboard wheel half having P/N 2607046, S/N 5899 
or greater, or S/N H-1722 or greater. And
    (2) Remove any outboard wheel half specified in paragraph (b) of 
this AD, and replace it with an outboard wheel half having P/N 
2607047, S/N B-5899 or greater, or S/N H-0864 or greater.
    (c)(1) An alternative method of compliance or adjustment of the 
compliance time that provides an acceptable level of safety may be 
used if approved by the Manager, Seattle Aircraft Certification 
Office (ACO), FAA, Transport Airplane Directorate. Operators shall 
submit their requests through an appropriate FAA Principal 
Maintenance Inspector, who may add comments and then send it to the 
Manager, Seattle ACO.
    (c)(2) Alternative methods of compliance, approved previously in 
accordance with AD 97-17-01, amendment 39-10102, are approved as 
alternative methods of compliance with this AD.

    Note 3: Information concerning the existence of approved 
alternative methods of compliance with this AD, if any, may be 
obtained from the Seattle ACO.

    (d) Special flight permits may be issued in accordance with 
sections 21.197 and 21.199 of the Federal Aviation Regulations (14 
CFR 21.197 and 21.199) to operate the airplane to a location where 
the requirements of this AD can be accomplished.

    Issued in Renton, Washington, on July 1, 1998.
Stewart R. Miller,
Acting Manager, Transport Airplane Directorate, Aircraft Certification 
Service.
[FR Doc. 98-18159 Filed 7-8-98; 8:45 am]
BILLING CODE 4910-13-U